Pressure-gage for pneumatic tires.



I. A. BOWDEN.

PRESSURE GAGE FOR PNEUMATIC TIRES.

APPLICATION FILED MAY l2. 1910.

Patented Sept. 1T, 1918.

M1112 ffm'mawdm,

UNITED STATES PATENT oEErcE.

JUNIUS `A. BOWDEN, OF -LOS ANGELES, CALIFORN'IA, ASSIGNOR TO A. SCHRADERS SON, INCORPORATED, OF NEW YORK, N. Y., A CORPORATION F NEW YORK.

rREssuRE-GAGE. Fon PNEUMATIC Trans.

Spcification of Letters Patent.

Patented sept. 17, 1918.

Application 'led May 12, 1910. Serial N o. 560,796.

To all whom t may concern:

Be it known that I, JUNrUs A. BowDE-N, a citizen of the United States, residing in the city of Los Angeles, county of Los Angeles, State of California, have inventedr new and useful Improvements in Pressure- Gages for Pneumatic Tires, of which the following is a specification'.

My invention relates to a pressure gage adapted -to be placed upon and retained in position for use at any time upon-the air inlet tube of a pneumatic tire; and the object thereof is to produce a simple and efficient device whereby the pressure in the tire can be quicklydetermined at any time, and a device in which the leakage of air when ascertaining the pressureshall be reduced to the minimum, and at all other timesprevented. A further object is to provide al gage on which the indicatorl gures can be easily read.

I accomplish these objects by the pressure-`v gage described herein and illustrated in the accompanying drawings inwhich,

Fig. 1 is a longitudinal central section of my gage positioned upon the tireand in its inoperative position. l v

Fig. l2 is a side elevation of my improved device in its operative position indicating the vpressure in the tire, f

Fig. 3 is a side elevation artly in section showing a slight modification whereby the tire mayl be inflated without removing the age. l g Fig. 4 is a longitudinal central section of a modified 'form of the (pressure gage. Fig. 5 is an enlarged etail of the top portion of the parts shown in Fig. 4.

In the drawings 10 4is a pneumatic tire which is provided with an air inlet tube 11 having the ordinary lcheck valve 12 therein,

all of ordinary construction. `Upon the air inlet tube 11 is screwed a tubular casing 13, the upper end of which is reduced in size as best shown in Fig. 1. Within the. lower portion of casing 13, and resting upon the top of the air inlet tube is a "washer 14, preferably of rubber, which when the casing-is screwed upon` the tube, makes an air tight joint between the parts. Below casing 13 is a lock lnut 15, which holdsthe casing locked upon the inlet tube, when the device is positioned for use. At the lower end of the reduced upper end of casing 13 is the check valve displacer 16 which normally holds check valve 12 ofthe tire unseated when the device is in place/thereon, as shown in the drawings. Surrounding the reduced upper portion of casing 13 is -a tubular casing 17 which is providedat the bottom thereof with an external annular flange 18 and an internal annular flange 19. Theupper portion of the enlarged lower portion of casing 13is externally threaded, and upon the sameis screwed a nut 20 having an internal annular flange 21', which flange is yadapted to rest upon the external annular flange 18 of casing 17, as shown in Fig. 1, and holds said casing 17 firmly secured upon casing 13. A lock nut 22-may be used to lock nut 20 upon casing 13. The upper end of casing 17 is externally threaded and upon the same is screwed a cap 23. A washer 24 preferably of rubber is interposed betweenl the cap andthe upper end of casing 17 to make an air tightjoint. This washer also extends over the top of casing 13when the device is in place on a tire and in its inoperative position as shown in Fig. 1, so as to prevent leakage of air between casings 13 and 17. The upper end of casing 13 is eXteriorly threaded and upon the same is screwed an adjusting nut 25. This nut forms an exterior flange on the upper end of the casing and forms an upper bearing for the helical spring 26, the lower end of which rests upon flange 19 of casing 17'. This nut fits betweencasings 13 and 17 and forms a'guide for casing 17 as it moves up-V wardly, whenthe air pressure is being taken. Within casing 13 is a long plunger 27, the upper end of which bears against the inner side of cap 23, when air pressure is exerted against the inner end thereof. Upon the exterior surface of the reduced upper portion of casing 13 is placed a'scale 28 (shown in Fig. 2) with graduations commencing at lthe inner end of the reduced upper end and wardly against the pressure of spring 26 at whatever point on the scale the lower edge of nut 20 registers, the mark there shown indicates thepressure of air in the tire. As shown in Fig. 2, the pressure is indicated as being pounds. This scale is graduated according to the pressure of the air operating against the tension of spring 26. When the device is new there will be more parts'than after it has been used for some time. By screwing'nutv25 to compress the spring a little more than it was compressed at irst it compensates for this reduced frictional engagement, and retains the accuracy of the device. In Fig. 3 I have. shown a charging inlet tube 29 which is with a check valve 30 and the outer end is screw threaded for the attachment ofthe hose of a charging pump not shown. The outer end of this charging tube is normally closed by a cap 31 .which is removed when the tire is to be inflated. In Fig. 4 I have shown a slight modification of my device.

In this modification I dispense with plunger 27 andjreduce the outlet at the outerend of casing 13 to a small hole 32, through which air passes and forces the outer casing outwardly against the tension of spring 26. I ,also place upon the internal flange 19 ofthe outer casing an elasticv packing or rubber washer 33, upon which spring 26 rests, thereby making a packed joint between casings 13 and 17 at thispoint. If desired this washer can be used in the construction shown in Fig. 1. I prefer the luse of plunger 27 as it has a working it in casing 13, and thereby reduces the loss of air when the air pressure is being taken. After the air pressure is taken, the operator presses on cap 24 and forces the outer casing back into its inoperative position as shown lin Fig. 1, and then screws nut 20 to lace and locks it with nut 22. When this is accomplished, there can be no loss of air as all the joints at which air can escape are packed. by suitable washers. By removing'the ordinary check valve in the air inlet tube, the displacer may be omitted.

Having described my invention what I claim is z- '1. A pressure gage for pneumatic tires, comprising a casingadapted to be attached to a valve and having an opening at its outer end, la pressure-responsive element therein, means for Jfastening said pressureresponsive element against movement, and means adapted to close the end of said casing against the passage of air, said fastening means, when operated to fasten said pressure-responsive element against move ment, being adapted to move and hold said closing means in closing osition.

2. A gage for pneumatic tires, comprising friction Ibetween .the moving and having 4an opening at;its outer end, a

`pressure-respt'insive element therein, means adapted to fasten said lpressure-responsive element against movement, said pressure-rei sponsive element closing air-tight the end of the casing when held in fastened position.

3. A gage for pneumatic tires, comprising a casin adapted to be attached to a valve, a springresisted plunger in said casing, said casing constituting a cylinder for said plunger, and afsleeve exterior of said casing actuated by said plunger, the sleeve and casing being one provided with a graduated scale and theother acting'as a pointer provided moving along said scale.l

4. A ygage vfor pneumatic tires, comprising a casing adapted to be attached to a said casing` valve, a plunger in said casing, constituting a cylinder for said plunger, and a sleeve slidable upon the exterior of said casing and adapted to lbe actuated by said plunger, degrees of pressure being represented by the relative positions of said .cas-

ing and sleeve, and a spring between said casing and sleeve for resisting pressure-responsive movement of said plunger.

5. A gage for pneumatic tires, comprising a casing adapted to be attached to a valve, a spring-resisted plunger in said casing, and a sleeve exterior of said casing and adapted to be actuated by said plunger', ldegrees of pressureJ being represented by positions of said casing and sleeve, and

having means thereon for the relative vmeans on said sleeve for fastening said vplunger against movement.

6. A gage for pneumatic tires, comprising a casing adapted tov beattached to a valve, a plunger in said casing, and a sleeve exterior of ysaid casing and adapted to 'l be said casing hav-v ing a shoulder at its outer end, .and said4 actuated by said plunger,

sleeve having a shoulder at its inner end,

and a spring between said sleeve and casing,

bearing at its ends`upon said shoulders.

7. A gage for pneumatictires, comprising a ca sing adapted to be attached to a valve, said casing having a contracted portion, a pressure-responsive member in the contracted portion of said casing, a sleeve exterior of said casing adapted to be operated by said pressure-responsive member, and meansv adapted to engage said sleeve and the larger portion of said casing -for fastening said pressure-responsive member against movement.

8. A gage for pneumatic tires, compris ing a casing adapted to be .attached to a valve, said casing having a contracted portion, a pressure-responsive 'member in the contracted portion of said casing, a sleeve exterior of said casing adapted to be operated by said pressure-responsive member,

and means adapted to engage said sleeve and have hereunto subscribed my name this 5th the larger portlon of said casing l:or fastenday of May, 1910. ing said ressure-res onsve mem er against movemenlt, and a ppacking adapted to be JUNIUS A' BOWDEN' pressed against said casing when said sleeve Witnesses:

and casing are connected together. G. E. HARPHAM, In Witness that I claim the foregoing I D. B. AUSTIN. 

